Older adults who are healthy and take antibiotics don’t have a heightened risk of cognitive impairment or dementia, a study published Wednesday in Neurology finds.
Past research has shown that antibiotics can disrupt the gut microbiome and have harmful long-term impacts on the brain, as the gut microbiome is imperative for overall health. Investigators assessed data on 13,571 healthy people who were older than 70. Being “healthy” was defined as not having dementia, heart disease, physical disabilities or life-threatening health problems that could reduce a person’s life by fewer than five years.
None of the participants had cognitive impairment or dementia during the first two years of the study. The people were followed for an average of five years more. Participants took cognitive tests when the study started, one year after and then every two years after. Over the course of the study, 63% of participants used antibiotics at least once.
During the additional five-year (on average) follow up span, 461 people developed dementia and 2,576 people developed cognitive impairment.
Researchers compared scores in those who took antibiotics and those who didn’t, and didn’t find a difference. The team also adjusted data to take into consideration medications that could affect cognition, family history of dementia and cognitive function at the start of the study. Still, there wasn’t a difference.
The team didn’t find any associations with antibiotic use over time, continued use and specific types of antibiotics.“Given that older adults are more frequently prescribed antibiotics and are also at higher risk for cognitive decline, these findings offer reassurance about using these medications,” Andrew T. Chan, MD, a study author from the Harvard Medical School in Boston, said in a statement.